This error was encountered in arrow, and a longer discussion may be found in apache/arrow#44342. On an arm machine I observe a segmentation fault inside background_thread_entry. Inspection of the disassembly points to the tsd_fetch_impl function. Unfortunately, due to the fact that I am observing this within the build of arrow that embeds jemalloc, I have not been able to do much to rebuild the binaries in any way that allows for easy debugging, and seemingly unrelated changes are enough to make the problem vanish (there's nothing nondeterministic about the error since it reproduces consistently under identical circumstance, but it does appear to be sensitive to very subtle changes in how things are built and run e.g. changes in Python import order and therefore library load order).